If you're feeling a bit claustrophobic on our current earth-sphere, I have some good news: high-speed space travel just got a little bit more feasible.
The photon is a strange particle (or wave!) Though it has no mass, it can still impart momentum. When you turn on a light, the photons from it collide with you, and actually physically move you. It is not detectable to our senses, but every time photons hit us, they exert a force upon us. Shine a strong enough flashlight on a ball, and it will roll. This is known as
radiation pressure (and FYI light is just a form of radiation.) With a strong source of light, such as the sun, and low gravity and friction, such as in the vacuum of space, radiation pressure is a viable means of transportation. This basic effect is the idea behind
solar sails, and has already been used in unmanned spacecraft, such as
Mariner 10. But that is all old hat.
It has been theoretically proposed that photons, in the form of lasers, can be amplified so that their thrust is greatly increased. In December of 2006, Dr. Young Bae did just that, by
building (and publicly demonstrating) the world's first Photonic Laser Thruster (PLT), which amplifies photonic thrust by a factor of 3,000. Not bad for a proto-type. The demonstration paper will be published in the peer-reviewed journal American Institute of Aeronautics and Astronautics (AIAA), is titled
Photonic Laser Propulsion: Proof-of-Concept Demonstration, and will be published later this year. Using several of these photonic thrusters together, spacecraft could achieve speeds of more than 100 km
per second. This technology is not far-and-away, it is already present, and is being refined for more efficient use. With current technology, the trip to Mars would take six months. With PLT, it would take
one week or less. Given that most of the hazards of interplanetary travel are risky precisely because of the length of the journey (radiation accumulation, bone deterioration, psychological stability), this just doesn't make interplanetary travel more comfortable, it makes it possible. There is still plenty of research and application to be done to be sure, but the deployment of these technologies will now be measured in years rather than generations.
A more practical application of PLT would be to maintain
exact satellite formation - by exact, I mean staying within formation to a
few nanometers, with the satellites spread out over
kilometers. An immediate use of this kind of technology would be to form the next generation of telescope-like devices - satellite formations like this could scour the depths of the universe at many orders of magnitude greater detail than the Hubble telescope - we could detect black holes for the first time, see planets and stars never seen before, and indeed peer into the very origins of the universe. Considering the
pictures from Hubble, think of what we could do with several orders of magnitude beyond this:
Of course these satellite formations wouldn't just take pretty pictures; more pragmatically, they would be able to search for rare minerals in asteroids, uncover precise details of our own solar system's planets and moons, and let us prioritize where our other efforts should focus.
And holy $hit, he's also made a lot of progress working on
nuclear fusion engines and researching a freakin' matter-antimatter engine. What's next for this guy, an
artificial quantum singularity engine?
I think the coolest part of this is that Dr. Bae is not a NASA scientist. He's just a really smart guy who loves to invent things, and started his
own institute to do so. On his own, he built his amplified photonic thruster - the first in the world -
with regular off-the-shelf products. It is becoming more and more clear that in the future it will be individuals and organizations that will lead the way in space exploration as much as it will be nation-states.
For a lengthy interview with Dr. Bae, check out this
podcast of the somewhat quirky
Space Show. The interview starts at 5:45.
For some reason this makes me inordinately happy: This weekend in Atlanta, there is a bowling tournament between Furries and Klingons. It's just like the Internet manifested in to reality! But of course, this raises an awkward question: which groups do the targs join? Their site mentions they are going to a meal afterwards. I would love to be able to watch their arrival... I wonder if anybody will try to substitute mayo for gagh?
Of course these satellite formations wouldn't just take pretty pictures; more pragmatically, they would be able to search for rare minerals in asteroids, uncover precise details of our own solar system's planets and moons, and let us prioritize where our other efforts should focus.
I'll be leaving early tomorrow for Canterbury, Kent, for a British Psychological Society conference. It should be hella killa. You know what they say about us social psychologists - we put the social in social psychology!
First you need to pick the berries. You could buy them of course, but that would be expensive, and not really the point of making your own cordial. Go find some in the woods - there are absolutely loads of berries out there. I think the optimal mix is 7:3 blackberries to elderberries but you could use mulberries, currants, blueberries, or any other kind you want. In a good spot you can pick 1000 g or more in less than an hour.
Put berries in a large pot, and fill the pot with water to just cover the berries. Cook over medium heat to reduce the level of liquid to the desired thickness. A potato masher or fork may be used to help crush the berries. Stir occasionally.
The longer you cook it the more concentrated your cordial will be. Usually you will want to cook off between 20% and 40% of the original level of liquid. This will take about 30 to 60 minutes.Once you have cooked down the berries, let them cool.
The next day, pour the mix out of one pot and into a fine-mesh sieve, draining into another pot below. Be careful not to splash juice everywhere!
Now we will add sugar and spices to the juice. You may vary the proportions for your taste, but high levels of sugar will keep it from spoiling, and taste normal once the cordial is properly diluted. If you decide to use low levels of sugar/no sugar, you will need to pasteurize the bottles once done (not covered here). I add (per 1000 g berries) 500 g of sugar, 20 cloves, and 2 cinnamon sticks. Allspice, nutmeg, and ginger would also be good additions. Add and stir until the sugar is dissolved. 
Once the mix has cooled to a non-scalding temperature, use a siphon or funnel to pour the cordial into the sterilized screw-top wine bottles. This can be messy, so cover anything that should not get sticky red juice on it! Distribute spices evenly between bottles.
To drink, pour a small amount in a mug and add hot water and rum/brandy if desired. Dilute cordial to taste, usually about 1 to 5. Delicious.What you see to the right (1 liter of cordial) was made from 1000 g of berries. 1500 g of berries would have filled the two bottles completely. When diluted, you can get about 10 to 20 mugs of cordial per bottle.
